Abstract: New polyether antibiotic A80438, its acyl and alkyl ester, alkyl ether and urethane derivatives, and salts thereof, are useful antibacterial and anticoccidial agents and increase feed-utilization efficiency in animals. Method of making A80438 by culture of Streptomyces bobili NRRL 15971 and synergistic compositions comprising (1) and A80438 compound and (2) nicarbazin, 4,4'-dinitrocarbanilide, certain napthalenamine and benzenamine compounds or metichlorpindol are also provided.

Abstract: New 3'" and/or 4'"-modified macrocin and 3" and/or 4"-modified-lactenocin derivatives of formula 1 have significant antibacterial activity. Compositions positions containing and methods of using these derivatives are also provided.

Abstract: C-20-Dihydro-deoxy-(cyclic amino)-derivatives of the macrolide antibiotics tylosin, desmycosin, macrocin, lactenocin, 2"'-O-demethylmacrocin and 2"-O-demethyllactenocin, which inhibit pathogenic bacteria, especially gram-positive bacteria, Pasteurella species, and Mycoplasma species, and pharmaceutical compositions thereof, are provided.

Abstract: Improved fermentation process for producing the gram-positive A-21978C antibiotics which comprises cultivating a new strain of Streptomyces roseosporus, NRRL 15998, and the biologically purified culture of this microorganism are provided.

Abstract: Antibiotic A42125, which is produced by a new strain of Nocardia aerocolonigenes, NRRL 18049, is a useful inhibitor of Gram-positive and methane-generating microorganisms. A42125 also increases feed utilization efficiency in ruminants. A biologically purified culture of N. aerocolonigenes NRRL 18049 and a method for producing A42125 by fermentation of this culture are provided.

Abstract: New alkaloids called hapalindoles, which are antibacterial and antifungal agents, and methods of preparing these alkaloids by culturing the blue-green alga Hapalosiphon fontinalis ATCC 39694, are provided.

Abstract: Antibiotic A41030, a complex of 7 individual factors, is produced by submerged, aerobic fermentation of new Streptomyces virginiae NRRL 12525, and Streptomyces virginiae NRRL 15156. The antibiotic factors are separated and possess antibacterial activity against Staphylococcus and Streptococcus species which are penicillin resistant. In addition, the antibiotic factors have shown inhibition of Streptococcus pneumonia Park I. The complex and the individual factors enhance feed efficiency in ruminant animals, and are growth promoters in chickens and swine, and are especially valuable in milk production in dairy cattle.

Abstract: Novel amines of formula:R--(CH.sub.2).sub.n --NR.sup.1 R.sup.2where R is cis-2-phenylbicyclo[2,2,2]octane or 2-phenylbicyclo[2,2,2]oct-2-ene nucleus, n is 1 to 3, R.sup.1 is C.sub.1-3 alkyl and R.sup.2 is hydrogen or C.sub.1-3 alkyl, and acid-addition salts thereof, which are useful for the treatment of disorders of the central nervous system.

Abstract: Novel glycopeptide antibiotics of formula (I) can be prepared from the glycopeptide antibiotics vancomycin, A51568A, A51568B, M43A and M43D by reaction with a ketone or aldehyde followed, if appropriate, by reduction. The new glycopeptide derivatives are useful antibacterial agents.

Abstract: A hitherto undescribed microorganism, Streptomyces virginiae NRRL 12525, which upon culturing produces the A41030 antibiotic complex comprising several factors. The A41030 antibiotics produced show antibacterial activity against the gram-positive genera Staphylococcus and Streptococcus which are resistant to penicillin. In addition, these antibiotic act to promote growth and improve feed efficiency in ruminant animals, poultry and swine, and other livestock, and to improve milk production in ruminant animals.

Abstract: New polyether antibiotic A80190, its acyl and alkyl ester, acyl ester and urethane derivatives, and salts thereof, are useful antibacterial and anticoccidial agents and increase feed-utilization efficiency in animals. Methods of making A80190 by culture of Actinomadura oligospora NRRL 15877 and synergistic compositions of the A80190 compounds with nicarbazin, 4,4'-dinitrocarbanilide, certain napthalenamine and benzenamine compounds and metichlorpindol are also provided.

Abstract: Improved fermentation process for producing the polyether antibiotic A80190 which comprises cultivating a new strain of Actinomodura Oligospora, NRRL 15878, and the biologically purified culture of this microorganism are provided.

Abstract: New glycopeptide antibiotic CUC/CSV which has the formula: ##STR1## wherein R is L-ristosaminyl;R.sub.1 is the disaccharide mannosyl-glucosyl; andR.sub.2 and R.sub.3 are mannosyl, and its salts, particularly the pharmaceutically acceptable salts, are useful new antibiotics are active against gram-positive bacteria and increase feed-efficiency utilization and enhance milk production in ruminants.

Abstract: New macrocin and lactenocin ester derivatives of the formula: ##STR1## wherein R is formyl or hydroxymethyl; R.sup.1 is hydrogen, acetyl or propionyl; R.sup.2 is hydrogen or ##STR2## and R.sup.3 is hydrogen, acetyl, propionyl, n-butyryl or isovaleryl; provided that one of R.sup.1 or R.sup.3 must be other than hydrogen; and the acid addition salts thereof; prepared by bioconversion of macrocin or lactenocin with an acylating enzyme system produced by Streptomyces thermotolerans strains, have improved activity against Mycoplasma species.

Abstract: Novel aracyl glycopeptide derivatives of formula 1 and methods for their preparation from the glycopeptide antibiotics vancomycin, A51568A, A51568B, M43A and M43D, are provided. The new glycopeptide derivatives are useful antibacterial agents.

Abstract: Novel glycopeptide derivatives of formula 1 and methods for their preparation from the glycopeptide antibiotics vancomycin, A51568A, A51568B, M43A and M43D, are provided. The new glycopeptide derivatives are useful antibacterial agents.

Abstract: C-20-Modified derivatives of macrolide antibiotics which include demycinosyltylosin (DMT), 20-dihydro-23-demycinosyltylosin (dihydro-DMT), 23-de(mycinosyloxy)tylosin (DMOT), 20-dihydro-23-de(mycinosyloxy)tylosin (dihydro-DMOT), 5-O-mycaminosyltylonolide (OMT), 20-dihydro-5-O-mycaminosyltylonolide (dihydro-OMT), 23-deoxy-5-O-mycaminosyltylonolide (DOMT), and 20-dihydro-23-deoxy-5-O-mycaminosyltylonolide (dihydro-DOMT) inhibit pathogenic bacteria, especially gram-positive bacteria, and Mycoplasma species; and pharmaceutical compositions thereof.

Abstract: A-21978C cyclic peptide derivatives of the formula ##STR1## wherein R is hydrogen, a specified aminoacyl or N-alkanoylaminoacyl group, 8-methyldecanoyl, 10-methyldodecanoyl, 10-methylundecanoyl, the specific C.sub.10 -alkanoyl group of A-21978C.sub.0 or the specific C.sub.12 -alkanoyl groups of A-21978C factors C.sub.4 and C.sub.5 or an amino-protecting group; and R.sup.1 is hydrogen, an amino-protecting group, or a specified aminoacyl or N-alkanoylaminoacyl group; provided that, when R is other than aminoacyl or N-alkanoylaminoacyl, R.sup.1 must be aminoacyl or N-alkanoylaminoacyl; and, when R.sup.1 is an amino-protecting group, R must be aminoacyl or N-alkanoylaminoacyl; and the salts thereof, are useful as antibacterial agents or as intermediates to antibacterial agents.

Abstract: Antibiotic A-21978 complexes, in particular the A-21978C complex, comprising microbiologically active, related factors C.sub.0, C.sub.1, C.sub.2, C.sub.3, C.sub.4, and C.sub.5. A-21978 complex and A-21978C complex are produced by submerged aerobic fermentation of Streptomyces roseosporus NRRL 11379. The individual A-29178C factors are separated and isolated by chromatography. The A-21978 and A-21978C complexes; the A-21978C factors; and pharmaceutically acceptable salts thereof are antibacterial agents and improve growth promotion in poultry.

Abstract: Antibiotic A-21978C complexes, in particular the A-21978C complex, comprising microbiologically active, related factors, C.sub.0, C.sub.1, C.sub.2, C.sub.3, C.sub.4, and C.sub.5. A-21978 complex and A-21978C complex are produced by submerged aerobic fermentation of Streptomyces roseosporus NRRL 11379. The individual A-21978C factors are separated and isolated by chromatography. The A-21978 and A-21978C complexes, the A-21978C factors, and pharmaceutically acceptable salts thereof are antibacterial agents and improve growth promotion in poultry.